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Hello,

Can I ask you what your usage of the golangci-lint fmt command is?

The golangci-lint fmt has been designed to format by default, because the formatting of the code is not optional.
The --diff is more related to CI.

Also, the formatters are run when using golangci-lint run, so the --diff option is less useful locally.

Not sure if I am doing something wrong but run command does not seem to check formatting issues for me.

For example, given this code:

// main project
package main

import (
	"fmt"
)

func main() {
fmt.Println("Test")
}

When I run the linter it reports no issues:

$ ./bin/golangci-lint run --default all --disable forbidigo
0 issues.

Once I run the formatter it does detect the formatting is wrong though:

$ ./bin/golangci-lint fmt --diff
diff /Users/maxnunes/Development/test-go-linter-fmt/main.go.orig /Users/maxnunes/Development/test-go-linter-fmt/main.go
--- /Users/maxnunes/Development/test-go-linter-fmt/main.go.orig
+++ /Users/maxnunes/Development/test-go-linter-fmt/main.go
@@ -6,5 +6,5 @@
 )

 func main() {
-fmt.Println("Test")
+       fmt.Println("Test")
 }

ok, it's because you are using the default formatter.

Use the following configuration to enable a formatter:

version: "2"

formatters:
  enable:
    - gofmt

that works, thanks!